Latest Posts

Climate Change & Species Migration

September 1, 2015
Steven Carruthers

On a recent visit to Northern NSW, I had a discussion with a grower about climate change. Global warming is a topic I have avoided over the years owing to a range of divergent views; even though 97% of scientists agree climate change is occurring. The skeptics argue that the climate models are unreliable or that human activity is playing a relatively minimal role in global warming. Given the number of catastrophic weather events in recent times, I was interested in what the grower had to say. I quickly came to realise that climate change is more than just about changing weather patterns. Read More »

Can I stop my Deep Flow Technique recirculating pump overnight?

September 1, 2015
Rick Donnan

Thank you for all the answers you gave me. I have just one short question if I may, in reference to the system in my previous question (4m x 20m DFT tank).

If I shut the pump down at night and only run it during the day time, do you think it will be ok in terms of oxygenation? I am planning to construct an additional three grow tanks each with its own pump, and would like to save a bit on energy costs by turning the pumps off at night.

(The previous question was answered in my August column. It related to the set up and management of a 20,000 litre Deep Flow Technique (DFT) system, which held an extremely high 13 litres of nutrient solution per plant.)

Answer by RICK DONNAN Read More »

HYDROPONICS: Great potential, but with challenges

September 1, 2015
Wageningen UR researcher Tycho Vermuelen examines a trial deep flow system.

In Europe, substrate culture and hydroponics are regarded as separate growing techniques, where substrate-less culture is known as hydroponics. In this article, the author examines the business case for developing new hydroponic systems that increase crop yields, and he highlights the bottlenecks and challenges for large-scale system developers.


Introduction to Commercial Greenhouse Crop Production

August 10, 2015

Powerplants Australia is presenting an ‘Introduction to Commercial Greenhouse Crop Production’ course on Wednesday 19 to Friday 21 August. This course is designed for industry participants who wish to gain a better understanding of the theoretical and practical issues associated with commercial greenhouse crop production. Read More »

New Food Paradigm

August 1, 2015
Steven Carruthers

With the fascination of images beamed back to earth of Pluto, and the discovery of an Earth-like planet located 1400 light years away in the Cygnus constellation, it seems appropriate that we continue the space theme with our story of eight aspiring astronauts cocooned in a Mars-like habitat on top of Hawaii’s Mauna Loa volcano. The aim of the mission was to study the group’s cohesiveness over the eight months of simulated long-duration space travel, to figure out how to pick a crew that works well together, that’s able to stay positive, happy and productive. The mission demonstrated that plants grown hydroponically not only supplemented a diet of freeze-dried food, but also had a positive effect on crew behaviour. Read More »

Setting up a DFT (Deep Flow Technique) system

August 1, 2015
Rick Donnan

I am setting up a DFT grow tank for lettuce in South America, first one, and then more in time. The size is 4m wide x 20m long and 25cm deep with a 1000L control tank. I have had five similar sized sub-irrigation tanks with gravel before, but this is my first DFT system. I want to use a swimming pool pump with a venturi to circulate and aerate the nutrient solution, and aim to do a total replacement of the grow tank volume every 2 hours. Where in the system would be best to place the pump? Between the control tank and the grow tank, pumping from the control tank into the grow tank with an overflow back to the control tank. Or the other way around? Answer by RICK DONNAN Read More »

From Soil to Substrate. . .

August 1, 2015

The development of the berry industry in Australia
Raspberry and blackberry production under protected cropping in Australia is set to expand. The forecast growth will come from new higher yielding varieties, year-round production, and increasing consumer demand for fresh, healthy, convenient and tasty berries. By JONATHAN ECCLES Read More »